Pattern lifting device



REDBL D. B. DIMICK PATTERN LIFTING DEVICE Original Filed Oct. 23. 1929 J 2 215mm 327%; on A fittornegs.

Patented Sept. 22, 1931 UNITED TATE PTA-TENT orricn.

DANIELXBAKLIER DIMICK, or BIRMINGHAM, ALABAMA f PATTERN LIr'rmo DEVICE Original application filed October 23, 1929, Seria1No. 401,767. Divided and this application filed December 26, 1939.

The present inventionrelates to'improvements in pattern lifting devices, and is a division of my copending application-Sen No. 401,767, filed October 23,; 1929, entitled (5 Method and apparatus for casting pipe. I

An object of the invention is to provide an improved pattern lifting device, whereby the pattern may be lifted from themold flask efiectively and conveniently, and in which great force is exerted to break the static friction existing between the pattern and the sand. 7

Another object of the invention lies in providing an improved pattern lifting device, in which the parts of my improved mold flask are availed of to cooperate with a novel form of lifting means, whereby initially greatly increased pressure is brought to bear upon the'pattern to start the same out of the sand. 7 7

With the foregoing and other objects in view, the invention will be more fully described hereinafter and will be more particularly pointed out in the claims appended hereto.

In the drawing, which shows only one embodiment of the invention,

, The figure is a fragmentary Vertical section of a mold flask, with the improved lifting device applied to the pattern preparatory to raising the same.

Referring more particularly to the drawing, 24 designates the cheek or outside retaining wall of the flask, and 26 represents the inner core arbor; between which parts the sand is rammed. The core arbor 26 may be provided with Wings 28 to support and hold the molding sand in place in the core of the finished mold.

The pattern is shown at 29. This pattern is constructed for the straight bore of the desired pipe and also for the outside of the bell of said pipe. The top portion of the pattern 29 is extended to receive means for withdrawing the pattern from the flask mold, and for this purpose, openings 30 are provided in the upper extended portion of the pattern. The outside stripping plate 37 is machined in bore to the outside diameter of the top or enlarged bell end of the pattern Serial No. 504,971.

the pattern. A weighted or massive cast iron cen.ering plug 39 rests upon the arbor 26' and within the inner stripping ring or plate 38.? The engaging surfaces ofthe plug 39 and stripping plate 38 are properlymachined, and the outside surface of the plug 39 is preferably tapered as shown. The outside stripping plate37 is held in place the use of clamps 40 in a well-known manner. The tempered molding sand rammed in place betweenrthe pattern '29 and cheek 24 is represented at 41, and the sand between the'pattern 29 and the arbor-26 is shown at 42.

Referring to the lifting device for the pattern, designates the hook ring, being part .ofthe pattern. drawing: mechanism, while 71 designates the .pattern hooks which are carried by the chains 72 and 73. Hold-down lugs 74 are welded or otherwise secured to 'thepattern hooks. .71;

A wooden or'metalbridge 75 is provided with'le'gs 76gwhich rest on the inside stripping plate 38.' The bridge isadapted to receive vertical pressure from the lugs 74, as hereinafter described. i

ln operation, the hook ring 70 is adapted to receive 'a power lifting crane hook. The wooden bridge 75 is placed with its two legs resting on the inside stripping plate 38. The hooks 71 are engaged in the'openings in the upper end of the pattern 29, and the lugs 74 rest upon the bridge 75. Liftingaction by the crane acting on ring 70 exerts an angular upward pull on the grab hooks 71. The lift-.

ing strain is exerted on straight lines through the chains 72 and 7 3,butbecause of the form hooks 71 will be.- prevented from taking aposition in alignment with thelengths of the chains 72 and 73. The lifting strain thereby exerts an inward circular force on the grab hooks 71 around the center of the lower circular hook partas an axis. This circular force is'resisted by the downward pressure of the lugs 74 against'the bridge 75.

lVith this appliance, the core and inside stripping plates 38 are held down, while the pattern isw ithdrawn'a suflicient distance to of the triangular orwedge lugs 74, the grab broken.

break the static friction between the bore of the pattern and the sand of the core. By the time the pattern is lifted a sufficient distance to enable the lugs 7 4 to clear the bridge 75, the friction between the pattern bore and the core is so reduced that there is no possibility of this friction being enough tolift the core against gravity with the pattern as it is further Withdrawn.

After the pattern 29 is completely removed from the mold, the stripping plates 37 and 38 are likewise removed. The centering plug 39 is, however, left in place. Subsequently, the completed flask mold is removed from the molding machine and placed on the pouring floor. c

i It willfbe obvious that various changes in the construction, combination and arrangement ofparts could be made, which could be used Without departing from the spirit of my invention, and I do not mean to limit the invention to such details, except as particularly pointed out in the claims.

holding the latter down during the initial movement of the pattern.

6. A lifting mechanism for drawing patterns from mold flasks, comprising catch devices for engaging the pattern, and means engaged by said catch devices, and engaging the inner stripping plate of the mold to hold the latter down while the pattern is being initially lifted by said catch devices.

7 A liftingdevice for drawing patterns from mold flasks, comprising a ring device for engagement by a crane hook, chains extending from said ring device, grab hooks on said chains for engaging the pattern, a bridge engaging the inner stripping ring of the mold, and lugs on said hooks initially engaging the bridge to force the chains out of line and for transmitting the initial lifting strains to clamp down the bridge upon the inner stripping plate.

DANIEL BAKER DIMICK.

Having thus described my invention, what I claim and desire to secure byLetters Patent of theUnited States is :c

1. A' lifting mechanism for drawin patterns from mold flasks comprising 'grabdmoks V for engaging the pattern having lugs, a bridge piece fitted in the flask upon the inner stripping plate and engaged by said lugs, and

means connected to the hooks for lifting the pattern and tending to rotate the hooks whereby to press the lugs firmly against the bridge.

2. A lifting mechanism for drawing pat- I terns from flasks comprising grab hooks adapted to engage with the pattern and having lugs thereon, a bridge piece having legs for engaging the inner. stripping plate of the flask and engaged by said lugs, chains coupled to said grab hooks, and a ring connected to said chains and adapted to be engaged by a hoisting mechanism. V 3. A lifting mechanism for drawing patterns from mold flasks comprising means for engaging and lifting the pattern, and means acted on by aportion of the first named means whereby to hold the flask and the inner stripping plate thereof while the static friction incident to the raising of the pattern is 4. A lifting mechanism for drawing. pat- 't'erns for mold flasks comprising hooks for engaging the pattern, a bridge engaging the inner stripping plate of-the mold, and means between said hooks and bridge for holding .down the stripping :plate during the initial movement of the pattern.

5. A lifting mechanism for drawing patterns from mold flasks, comprising catch devices for engaging the pattern, lugs on said catch device, andmeansengaged by said lugs and engaging the inner stripping plate for 

